Stanly County authorities say a 15-month investigation into illegal use of prescription narcotics has led to the arrest of 25 suspects.

The investigation, which began in mid April 2013, involved the Stanly County Sheriff’s office, the SBI, Albemarle police, and law enforcement agencies from several surrounding counties, according to investigators.

Suspects ranged in age from 22 to 65 and came from Stanly, Anson, Montgomery and Union counties. In one case, investigators said, a suspect was accused of dealing drugs within 1,000 feet of a school.

The suspects face a total of 120 charges, with bonds ranging from $1,500 to $2.5 million. The arrests took place between April and July of this year, detectives said.